in reply to Logical Not not working!!!

Rather than using a C-style for-loop, a more Perlish way of dealing with the array is as follows:
use strict;
use warnings;
use Data::Dumper;

my @array = (1,0,1);

for my $item (@array) {
    $item = !$item + 0;
}

print Dumper(\@array);

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$item becomes an alias for each element of @array: so whatever you do to $item you really do that to the actual element of the array.

Update: or even shorter, but perhaps less legible:

$_=!$_+0 for @array;

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CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In Section Seekers of Perl Wisdom